Root Letter is absolute fucking garbage. Only cleared one route so far but:

It sounds like it has potential: Protagonist had a
pen pal 15 years ago when he was in high school. When clearing out his
old room he finds an unopened letter from her that says "I killed
someone. Goodbye" and he heads to her hometown to investigate, using her
old letters to find her old classmates, who all insist there's no such
person. Cast is all veterans like Hidaka Noriko and Inoue Kikuko, and
the game's system is an old-fashioned command-type adventure.

System-wise it's TOO old fashioned and is straight up
just an ADV from 20 years ago complete with pixel hunting and retarded
leaps of logic.

And then there's the writing. Ohhhhhhhhhhhhh boy the fucking writing.

The main character's an absolute idiot who takes far
too long to figure out that his pen pal was using a fake name even after
they hand you all the fucking evidence you need to figure this out.
He's also a crazy fucking asshole without the slightest bit of common
sense. The "mystery" is something you can figure out almost
immediately and despite everyone trying to hide it super hard it turns
out to be ABSOLUTELY FUCKING NOTHING. And actually, are they even trying to fucking hide it, because the excuses they give you are "it was a ghost" "it was aliens" "IT WAS
YOUKAI" and the retarded protagonist takes all of these seriously and
spends the next fucking chapter/day investigating whatever the
previous day's retarded nonsense was (by visiting real-life museums and
shit to promote tourist attractions in Shimane prefecture which worked with them on making this game). It's a glorified fucking tourism ad.

Oh and the pen pal has some pretty fucking great nicknames for her "best friends".

Hidaka Noriko: "I have seven best friends and we're
the bestest of friends ever! They all have nicknames, like FATASS,
MIDGET, APE and SLUT!"

And the protagonist uses these nicknames too so he
goes up to a newscaster and screams at her "HEY YOU'RE THE SLUT, I KNOW
YOU'RE THE SLUT, ADMIT IT YOU SLUT" (in Japanese it's actually ビッチ/bitch but the nuance is more like English "slut" than "bitch).

The classmates are all fucking psychopaths too. Bald glasses guy is a crazy cat man and a stalker and embezzles money, ape has violent tendencies, best friend is nuts, fatass somehow has PTSD from Shiori's fake suicide even though HE WAS THE ONE WHO SPOTTED THAT THE BLOOD WAS FAKE, midget tried to rape Shiori but thinks there's nothing wrong because he only TRIED and didn't actually do it and is a knife-wielding maniac, and when glasses wants to kill himself because he can't cover the funds he embezzled together they all decide to cover it for him, except they force the main character to cover a third of all of it.

So uh yeah.

Root Letter is fucking garbage written by a literal lunatic

Also I know I might be making this sound like it's so bad it's actually good but it's REALLY not because 90% of the
playtime is going to an area, having the protagonist say something
ridiculously fake about how great the tourist attractions in Shimane
prefecture are, and going "well there's nothing here, maybe I should go
to X next!"and then he does this same fucking thing several times before finally running into a character who'll actually advance the plot, slightly. It's mind-numbing.

Googling it in English has people claiming it's a "murder mystery". AHAHAHAHAHAHAHAHA nope.

Fuck I'll just spoil it:

Aya died 25 years ago and her mother went nuts
The pen pal's real name is Shiori and Aya's father got her to pretend to be Aya and talk to Aya's mother as therapy or whatever.

The mother found "Aya" a pen pal, that's the main character.

The mother died in a fire in an accident and Shiori
quit being Aya 15 years ago. Shiori noticed there was a problem with the
wiring in Aya's parents' house which led to the fire but didn't warn
anyone about it and blames herself for Aya's mother's death (that's the person
she "killed").

After Aya's mother dies she just decides to put an end to pretending to be Aya by pretending to commit suicide because she can't just stop, she has to traumatize her friends by pretending to slit her wrists complete with fake blood, because I don't even fucking know why.
Shiori's classmates all hide her existence from the
main character because... I don't know, they're crazy or fucking
retarded or something?

After spending ten days sightseeing in Shimane the
classmates go "eh alright we know someone who knows where she is" and
they go see him and he tells you Shiori moved to Africa. THE END.

Now, that's just the first route, and clearing it unlocks more routes, but after this fucking travesty I don't think I'm going to continue playing this. Also, one of the routes I unlocked was titled "government conspiracy"which is making me think this goes full fucking retard, Shin Hayarigami style, and fuck that.

Fuck this game.

Edit: Oh man I keep recalling more retarded shit in this game.

At one point you need to coax the crazy cat man to give you info by giving him a rare cat keychain. You find one on a cat's collar and try to steal it from the cat. The cat's owner shows up and thanks you for playing with her cat. The main character then says "sure NOW GIVE ME SOMETHING TO MAKE UP FOR IT". What the actual fuck is wrong with this guy? Hell, what the actual fuck is wrong with the writer who came up with this? I can't even begin to understand the sort of thought process that churns out this rancid shit

Edit: Turns out that from the second playthrough and on there's an option to skip entire chapters which makes checking out the rest of the game not that annoying (though it's not without its problems: It skips one of the letters for some reason, and you can't skip chapter 8).

Cleared the enmusubi route which is the "true" ending which adds a few more details, namely that Shiori's classmates are all horrible horrible people and the real reason Aya's mother died was because she ran back into the burning house because she's crazy and thought Aya was still alive. Shiori's fake suicide thing was because her classmates were all horrible assholes so that covers her motive but it still makes no fucking sense and it's all still fucking retarded. They add some stupid shit about how the reason the classmates were hiding Shiori from the main character was because they didn't want to get scandals or whatever from how they drove her to suicide except IT WASN'T SUICIDE DAMN IT THIS MAKES NO FUCKING SENSE. In this ending Shiori is a nurse and the main character just marries her and they live happily ever after.